戊酸雌二醇对去势大鼠阴道雌激素受体亚型α、β表达的影响

Effect of estradiol valerate on expressions of estrogen receptor-alpha and-beta in vagina of ovariectomized rats

目的通过研究戊酸雌二醇对去势大鼠阴道雌激素受体(estrogen receptor,ER)亚型α、β表达的调节,探讨雌激素受体亚型与绝经期泌尿生殖道萎缩的相关性。方法4月龄SD雌性大鼠80只,分为正常组、假手术组、去势组、药物干预组,每组20只。药物组大鼠于术后4周每天戊酸雌二醇灌胃给药,其余3组给予等量生理盐水灌胃。8周后处死大鼠,分离摘取阴道进行ERα、ERβ免疫组织化学染色及mRNA半定量RT-PCR检测。结果①ERα、ERβ在正常阴道鳞状上皮细胞、基质纤维细胞、血管内皮细胞、平滑肌细胞核及细胞质中均有表达,以阴道鳞状上皮细胞表达最强,且ERβ较ERα表达弱(P<0.05)。②去势组ERα较正常组、假手术组表达减弱(P<0.05),ERβ表达减弱更为明显(P<0.01)。③药物干预组ERα表达较去势组明显增强(P<0.05),与正常组、假手术组比较无显著差异(P>0.05),ERβ表达无明显增强。结论ERα是大鼠阴道优势表达的雌激素受体亚型;去势后阴道ER亚型表达下调,以ERβ明显;戊酸雌二醇可明显上调去势大鼠阴道ERα的表达,但不上调ERβ的表达。

Objective To investigate regulative effect of estradiol valerate on the expressions of estrogen receptor-alpha （ERα） and -beta （ERβ） in the vagina of rats after ovariectomy. Methods A total of 80 adult female SD rats weighing about 340 g were randomly and equally allocated into 4 groups ： normal control group, sham operation group, ovariectomized group and drug group. Estradiol valerate （ 1.2 mg·kg^-1·d^-1 ） was given to the drug group for 4 weeks by gavage in 4 weeks after ovariectomy. Rats from the other 3 group administered normal saline of same volume by gavage at same time period. Immunohistochemical methods were used to determine ERα and ERβ in superficial and deep compartments in the vagina. The mRNA expression levels of of the 2 subtypes were measured by semi-quantitative RT-PCR. Results ERα and ERβ were expressed in squamous epithelial ceils, stromal fibroblasts, vascular endothelial ceils, and smooth muscle ceils, and most in rats. ERα and ERβ expressions are down-regulated in the vaginal tissues after ovariectomy. Our findings show that estradiol valerate can up-regulate the expression of ERα but ERβ.